ILRI veterinary epidemiologist Jeff Mariner presents his research at a meeting of the World Animal Health Organisation (OIE) (photo credit: OIE).
Lauren Everitt of AllAfrica interviewed Jeffrey Mariner, a scientist at the International Livestock Research Institute (ILRI) in Nairobi, Kenya, about a current article he co-authored in Science (13 Sep 2012) on lessons learned in the eradication of rinderpest.
Mariner described how, while working at Tufts University, he tweaked a proven rinderpest vaccine to make it temperature stable so it could survive transport in Africa’s extreme temperatures—a critical development.
However, the scientist credits the eradication achievement to his team’s results-oriented focus, reliance on tried-and-true science and willingness to forge partnerships with local communities. He said he is taking the lessons learned from rinderpest and applying them to his newest challenge—tackling a disease killing off goats and sheep across Africa.
‘Most of us have heard of smallpox, the only other disease to be completely eradicated, but few people are as familiar with rinderpest. Could you describe the disease and why it was selected for eradication as opposed to foot-and-mouth disease, for example?’
Mariner: ‘It’s a German term so “rinder” is cattle and “pest” means plague, which translates to “cattle plague” in English. And it’s a highly fatal diarrheal disease so animals that were infected would generally die within a week … up to a 90 percent fatality rate. . . .
‘This is only the second disease in history to be completely eliminated, and the first ever livestock disease. Why was your team successful where others have failed?’
Mariner: ‘. . . We’re getting much smarter in two senses: One was how we delivered vaccines. We started to work through the community and local health workers. The other sense was about targeting our approach, thinking about the key populations for the transmission of rinderpest and then focusing our resources on those. . . .
If you do want to do global eradication, you have to do the hard places as well as the easy places. And having solutions for the most challenging places is the crux of eradication.
‘The first vaccine created for rinderpest worked, but it had to be refrigerated—making transport to rural African areas nearly impossible. What other false starts and challenges did you have to contend with?’
Mariner: ‘The vaccine we started with was an amazing vaccine . . . —it just had to be kept cold. Our idea was to take that vaccine and to just change the way it was freeze dried, effectively repackaging the vaccine. . . .
The challenge for us was that the idea was so simple. . . . [W]e actually had trouble generating attention for what we were doing. We had this solution to the problem but it wasn’t the kind of thing that got you in Science because it wasn’t some bizarre, novel approach. It was just a good, basic approach using an existing product and very focused on a solution. . . .
‘I’m applying the same approach to peste des petits ruminants (PPR), which is a disease that affects sheep and goats with the same issues as rinderpest, such as high mortality rates. I’ve taken that vaccine and used the same approach, and I got the same questions when applying for funding: Why are you using this old technology? If this was really going to work, wouldn’t someone have already done it by now? And I gave them the answer that I was told the same thing years ago and we eradicated rinderpest. . . .
‘From the article it’s clear that scientists relied on nomadic herders to help in eradicating rinderpest. Could you talk about the role they played and how scientists leveraged their knowledge?’
Mariner: ‘Their knowledge was key in two senses. One, they were very good at identifying rinderpest. It’s such an important disease for them that they had names for it. They could describe it. It was part of their oral history. The history would actually be handed down from fathers to sons about the different names of the disease. And you could talk to them about how it was behaving in the community, where it had been last year, where it was last week, and they could tell you where it was today. When we figured that out it was much easier for us to target the programs because we were able to use their information to know where we needed to focus. . . .
When we came up with the idea of training them to vaccinate, they were very receptive. They couldn’t dream of anything more exciting than going to a training course to vaccinate their own cattle. It was amazing. Although most of them weren’t literate, we were teaching them by demonstrating and step-by-step training and with some infographic materials. They were very interested and very good learners, and they handled the vaccine very well and were able to do those complicated steps, such as rehydrating the vaccine and using the proper time interval.
‘And because they were vaccinating their own cattle, they did it properly. . . .
‘In order to eradicate a disease you need widespread buy-in; people in diverse parts of the world must allow their livestock to be vaccinated. Did you meet with any pockets of resistance or groups that were reluctant to vaccinate their cattle? If so, how did you deal with them?’
Mariner: ‘. . . The area where we actually met resistance was in more conventional circles like veterinary services. Convincing them that they needed to hand over vaccination activities to illiterate herders was often a major policy challenge that we had to struggle with over the years. The veterinary profession is rather conservative, and there’s lots of talk about ethics—what you can hand over to who, and who can inject and those sorts of things. We had to contend with “I have a medical degree, and they don’t” and all those kinds of questions.
We were also trying to help people understand that what’ s appropriate in the developing world maybe isn’t appropriate in the first world, and what’s appropriate in the first world may not be appropriate in the developing world. If you insist on certain practices, you’re actually denying millions of people service. . . . And for us it was very clear that farmers all over the world could handle their own livestock and were doing a super job when they had training, so they should be given power to do that.
‘. . . Many of us have heard of avian flu and mad cow disease yet the eradication of rinderpest in 2011 went largely unnoticed. It could be argued that rinderpest has a larger impact on the human condition than some of these other diseases – any thoughts on why it received so little attention?’
Mariner: ‘. . . [Part of the reason is that the] international community, the animal health community, dropped the ball. When rinderpest was eradicated, this was a tremendous achievement, and it also showed that the animal health profession could really do something complicated and useful. But the major international players didn’t make proper use of the event. So a part of that is our fault as a profession—that we didn’t carry that message forward in a correct way and with enough enthusiasm about it.
One of the many problems that we had with rinderpest was that many times donors or governments would say that these countries don’t have the capacity to eliminate it. They would ask, “So why should we give them money when it’s going to be wasted?” With rinderpest they proved they could do it, they proved they could use the investment, but the message didn’t get carried on that they have that capacity.
‘What next? Now that you’ve eliminated rinderpest have you set your sights on eliminating another pestilence?’
Mariner: ‘We have. It’s peste des petits ruminants (PPR), also known as “goat plague.” There’s international interest in developing a progressive, controlled program. It’s a disease that’s high impact, and it’s also spreading. It’s across Africa, it’s across the Middle East and South Asia, it’s even reached to places like China in the last couple years, so it’s a disease that’s spreading. It affects small ruminants (sheep and goats), which are actually a very important species for the poor. Small ruminants are marketed much more easily so they have a lot more to do with household food security than cattle.
So we’re working on taking the lessons from rinderpest and developing those to help control and eventually eradicate PPR. I’ve been working in the lab to make the PPR vaccine thermally stable, and we have succeeded with that.
‘Now we’ll bring it into the field to look at different approaches to vaccination, similar to what we did with rinderpest, looking at how to involve the community and rural health workers in the remote areas and private practitioners. How do we combine all of those parties into public-private partnerships? And we’re starting to go back to Uganda and to Sudan again—I’m leaving for Sudan next week.
‘Where there any key lessons that you took from your work with rinderpest that you’re going to apply moving forward?’
Mariner: ‘The two situations are remarkably similar. PPR has a good vaccine that just needs to become more stable. The key issues are again how to do the vaccination, and what’s the right way to combine the community and the veterinarians and so that everyone works together to accomplish the task. The other is: which are the key populations that we need to vaccinate? How do we target the vaccination to get maximal impact? So those are the epidemiological and sociological research questions, if you like, and that’s really where we need to focus our efforts now. . . .’
Read the whole interview at AllAfrica: African herders help eradicate deadly livestock disease, 13 Sep 2012.
Read the ILRI News Blog about this: New analysis in ‘Science’ tells how world eradicated deadliest cattle plague from the face of the Earth, 13 Sep 2012.
Read the paper in Science (subscription required to read full text): Rinderpest eradication: Appropriate technology and social innovations, by Jeffrey Mariner, James House, Charles Mebus, Albert Sollod, Dickens Chibeu, Bryony Jones, Peter Roeder, Berhanu Admassu, Gijs van ’t Klooster, 14 September 2012, Vol. 337 no. 6100 pp. 1309–1312, DOI: 10.1126/science.1223805.
Read previous articles on the ILRI News Blog about the eradication of rinderpest: